Lutetium (177Lu) DOTA (177Lu-DOTA) (177Lu-DOTA)

DOTA-chelated lutetium-177 is a radiotherapeutic complex consisting of the radioisotope Lutetium-177 coordinated by the macrocyclic chelator 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA). It is not a biological target but rather a therapeutic moiety used in Targeted Radionuclide Therapy (TRT) to deliver localized ionizing radiation to malignant cells (PubChem, 2024). The complex is typically conjugated to a targeting ligand, such as a peptide or small molecule, which directs the radiation to specific receptors overexpressed on tumor surfaces, such as somatostatin receptors or prostate-specific membrane antigen (FDA, 2018). Once the drug binds to the target cell and is internalized, the Lutetium-177 isotope emits beta particles that travel short distances, inducing lethal DNA damage and apoptosis in the tumor while sparing distant healthy tissues (Journal of Nuclear Medicine, 2015). This dual-purpose complex also emits gamma radiation, enabling clinicians to perform real-time imaging and dosimetry to monitor treatment efficacy and safety (NIH, 2023). Its application has revolutionized the treatment of advanced neuroendocrine tumors and metastatic castration-resistant prostate cancer.

Other names

177Lu-DOTALutetium-177 DOTADOTA-Lu-177Lutetium-177-tetraxetan177Lu-tetraxetan

DOTA-chelated lutetium-177 acts as a cytotoxic payload that delivers localized ionizing radiation. The Lutetium-177 isotope undergoes beta decay, emitting electrons with a mean energy of 133 keV and a maximum range of approximately 2 mm in tissue (Journal of Nuclear Medicine, 2015). These beta particles cause ionizing radiation damage, primarily through the creation of double-strand DNA breaks in the cells to which the complex is delivered, leading to cell cycle arrest and apoptosis (NIH, 2023). Additionally, it emits low-energy gamma rays (113 keV and 208 keV), which are utilized for SPECT imaging and dosimetry (FDA, 2022).